Bad days, we all have them. Something happens, and suddenly you find yourself briefly but uncomfortably at odds with the world. I was having such a day myself recently – "a terrible, horrible, no-good, very bad day", to borrow a phrase from children's author Judith Viorst – until a honeybee arrived to put my world to rights.

Head down in a client’s garden, I heard its wing-light zeppelin hum before looking up just in time to spot it landing on the silver-blue flowers of a catmint plant.

The plant, in full bloom and still in its pot, had come fresh from a nursery, one of a dozen or so that I was busy placing into a sunny bed. I'd chosen Nepeta 'Kit Cat' for its floriferous habit, its pretty, long-lasting blooms and its soft, grey, aromatic foliage.

The honeybee however, had more important things on its mind, namely harvesting every drop of sweet nectar from those dainty-lipped flowers.

The contented hum of that lone bee was soon joined by those of a dozen more, all similarly in search of food. Lost in the moment, absorbed in observing the bees’ dexterous harvesting, I forgot my bad mood.

Instead I began wondering exactly where they’d come from and how far they’d travelled, marvelling at how adroitly and swiftly they’d detected the catmint’s arrival in an urban garden where, up to less than an hour ago, there had been almost no flowers.

As a gardener, it was cheering to see how quickly the plants had earned their place in the city’s complex ecosystem. Their good looks and fragrance aside, honey would soon be made from their sugary nectar, helping to keep the hive alive during the winter and providing healthy, delicious food for the beekeeper, whoever he/she was.

Honey aside, we all know that the more bees there are, the better it is for everyone. It’s good for nature, obviously: more bees encourage greater biodiversity. It’s also clearly good for mankind, resulting in more pollination and thus more food crops.

But my meeting with the honeybees that day reminded me that they have a value far beyond this. Distracted by their busy hunt for food, I stopped worrying, and began to relax, a well-known phenomenon that has led the world’s scientists and health professionals to study the ways in which regular exposure to nature benefits our health.

Examples include Attention Restoration Theory (ART) and Stress Recovery Theory. Both rest on the idea that nature is restorative, curative, protective, and the more we are exposed to it, the less prone we are to illness.

Studies prove that people exposed regularly to nature experience more positive emotions, improved memory function and concentration levels, even faster recovery periods after surgery.

Levels of the stress hormone cortisol also decrease, as do instances of impulsive, risky behaviour. In short, nature makes us nicer, healthier people.

More recently, there has been a broader movement to not only understand nature’s great value to mankind, but to put an actual monetary value on it, a concept known as ‘natural capital’.

Founded in 2006 and pioneered by researchers from Stanford University and the University of Minnesota in partnership with the Nature Conservancy and the World Wildlife Fund and leaders around the world, the Natural Capital Project aims to encourage society, and in particular big business, to radically shift perspective and view financial investment in nature – rather than its exploitation – as not only fundamental to human health, but essential to continued economic growth.

Looked at this way, the importance of bees as pollinators, or the restorative effects of an afternoon spent in the garden, are both pieces of the same giant jigsaw.

As to the question of how we put a true price on nature, it's a tricky one with which many great minds are grappling. To quote Indian banker Pavan Sukhdev of the international project TEEB (The Economics of Ecosystems and Biodiversity), "When did the bees last send you an invoice for pollination?" But a relatively recent (2008) conservative estimate put the annual value of Ireland's natural capital at €2.6 billion.

Clearly, as gardeners, we have a very important role to play in the protection of the country’s natural capital, whether it’s something as simple as fostering a biodiverse garden that’s home to richly varied yet interdependent habitats (ponds, trees, wildflower meadows and native hedgerows, for example) or minimising our use of hard, impermeable surfaces and damaging chemicals.

On a broader level, if you'd like to know more about this brave new global endeavour, get in touch with Hannah Hamilton, secretary of the Irish Forum on Natural Capital (naturalcapitalireland.com).

A voluntary group which brings together a wide range of organisations and individuals from the public, private, academic and NGO sectors, the forum was established earlier this year (membership is free) with the aim of helping to make nature count.

This week in the garden…

Order seed of winter salad and oriental leafy crops for sowing into modules and transplanting outdoors this month. All of these crops enjoy a fertile, moisture retentive, weed-free soil in a sheltered, sunny spot and will need to be kept well -watered during dry periods to prevent them from bolting. Recommended online Irish seed stockists greenvegetableseeds.com, brownenvelopeseeds.com, seedaholic.com and mrmiddleton.com

As the fruit on plum trees starts to swell and ripen, the weight of the crop can cause branches to split/ break. Prevent this from happening by supporting heavily laden branches with cable ties and/ or strong stakes. Branches that have already snapped under the weight of ripening fruit should be pruned back to undamaged wood, ideally to a point where the tree natural forks.

August is a good month to take semi-ripe cuttings of tender perennials such as pelargoniums, penstemons, argyranthemums and plectranthus as well as culinary herbs such as rosemary, thyme, sage, bay and hyssop.

The term “semi-ripe’ refers to the fact that the cuttings (typically 10-15cm long) are taken from this year’s growth at a stage when the tip of the cutting is soft but the base is hard.

The cuttings will need to be overwintered under cover of a glasshouse/ polytunnel for potting on and planting out next spring. See rhs.org.uk for detailed instructions.